According to a recent scientific review, marijuana and other drugs do not pose the same danger as was portrayed by laws written more than 50 years ago.
Since the passage of the Controlled Substances Act (CSA) in 1970, U.S. drug laws have been dictated by rigid categories that supposedly reflect the dangers posed by different substances—but the new study suggests that “drug policy contradicts expert assessments of drug harms” both in America and across the world.
The results indicate that governments’ legal rankings for substances bear little resemblance to what experts actually know about which drugs cause the most harm—something that cannabis consumers and much of the general public have long recognized.
For decades marijuana, for instance, was listed in the U.S. as Schedule I drugs. Although President Donald Trump issued an executive order last month directing his attorney general to complete the transition of cannabis from Schedule I to Schedule III, this has yet to happen.
A new article published in December 2025’s Harm Reduction Journal by a panel of researchers, clinicians, and individuals with experience with substance abuse found that the federal drug policies are “poorly aligned” with the scientific evidence and frequently contradict expert assessments of risks.
Researchers used the multi-criteria approach to arrive at their conclusion. Seventeen experts evaluated the harms of 19 drugs commonly abused across 18 different categories, from death by overdose and permanent health problems to disruptions in families, crimes and costs. Each drug’s harm was ranked by weighting and scoring.
The study—titled “US drug policy does not align with experts’ rankings of drug harms: a multi-criteria decision analysis”—also found that nearly all drugs were more harmful to the people who use them than to others, a result with significant policy implications. The authors say that a variety of harm-reduction strategies must be taken into consideration, noting the correlation between punitive measures and an increase in overdoses rather than a decline in drug use.
These findings come at a time when officials from the federal government and states are re-evaluating longstanding policies on drug control, sentencing, and public health.
For example, cannabis is rated less harmful that its Schedule I designation suggests.
By placing cannabis in the most restrictive legal category—while ranking fentanyl lower in Schedule II and leaving alcohol outside the federal drug scheduling system entirely—U.S. Policy has resulted in a system that, according to its authors, no longer reflects scientific consensus nor actual risk for the population.
They wrote: “Resources must be focused on wellness and health, not incarceration.”
Taken together, the study paints a picture of a drug policy frozen in time—one that treats substances like cannabis and psilocybin as major threats while failing to adequately respond to the substances doing the greatest damage. The authors argue that as fentanyl-related deaths continue to rise and alcohol harms remain, aligning laws with the evidence should no longer be a concern of academics, but rather a matter of public health.
Many jurisdictions still punish people for using cannabis and silocybin, despite the fact that they are potentially medicinal and have less danger than other drugs.
Researchers argue that evidence-based schedules could help shift the focus away from punishment and towards harm reduction and expanded access to treatment, as well as public health interventions. This is especially true for alcohol and fentanyl.
The authors note that “fentanyl is the most harmful of all drugs” and point to data supporting distributions of naloxone test strips, as well as supervised consumption areas.
The authors call for a deeper examination and write, “This research provides a useful start for future U.S. work that can account for other drugs, drug benefit, vulnerable subpopulations, (e.g. youth), as well as various methods and routes of consumption.”
This work, taken together, can help advance the scientific debate on the best way to minimize harms for people who abuse drugs while also addressing societal effects.
This study follows the Trump Administration’s decision to back away from its prior recommendation that alcohol be consumed in specific quantities, even though marijuana is still federally illegal and many Americans choose cannabis to improve their health.
Further changes will also be coming. The President signed into law a bill last year that contained provisions removing barriers for research to be conducted on marijuana, psychedelics, and other Schedule I drug risks and benefits.